As Arlene told us, “It’s just chemistry,” and detailed the properties of synthetic chemicals that have half-lives of two-thousand years, I harkened back to my organic chemistry experience in college which was less than successful for me (I’m not a very good cook, either). This time it was fine, she made it easy to understand.

The good news, as she explained, is that it’s easy to understand the health challenges of certain chemicals in terms of classes of chemicals, rather than specific ones, and there’s a web site, aptly named SixClasses.org to walk you through them, in short order (15 minutes).